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<b>DB-&gt;set_h_nelem</b>
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<b><pre>
#include &lt;db.h&gt;
<p>
int
DB-&gt;set_h_nelem(DB *db, u_int32_t h_nelem);
<p>
int
DB-&gt;get_h_nelem(DB *db, u_int32_t *h_nelemp);
</pre></b>
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<b>Description: DB-&gt;set_h_nelem</b>
<p>Set an estimate of the final size of the hash table.</p>
<p>In order for the estimate to be used when creating the database, the
<a href="../api_c/db_set_h_ffactor.html">DB-&gt;set_h_ffactor</a> method must also be called.  If the estimate
or fill factor are not set or are set too low, hash tables will still
expand gracefully as keys are entered, although a slight performance
degradation may be noticed.</p>
<p>The DB-&gt;set_h_nelem method configures a database, not only operations performed
using the specified <a href="../api_c/db_class.html">DB</a> handle.</p>
<p>The DB-&gt;set_h_nelem method may not be called after the <a href="../api_c/db_open.html">DB-&gt;open</a> method is called.
If the database already exists when
<a href="../api_c/db_open.html">DB-&gt;open</a> is called, the information specified to DB-&gt;set_h_nelem will
be ignored.
</p>
<p>The DB-&gt;set_h_nelem method
returns a non-zero error value on failure
and 0 on success.
</p>
<b>Parameters</b> <br>
 <b>h_nelem</b><ul compact><li>The <b>h_nelem</b> parameter is an estimate of the final size of the
hash table.</ul>
<br>
<br><b>Errors</b>
<p>The DB-&gt;set_h_nelem method
may fail and return one of the following non-zero errors:</p>
<br>
<b>EINVAL</b><ul compact><li>If the method was called after <a href="../api_c/db_open.html">DB-&gt;open</a> was called; or if an
invalid flag value or parameter was specified.</ul>
<br>
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<b>Description: DB-&gt;get_h_nelem</b>
<p>The DB-&gt;get_h_nelem method returns the estimate of the final size of the hash table.</p>
<p>The DB-&gt;get_h_nelem method may be called at any time during the life of the
application.</p>
<p>The DB-&gt;get_h_nelem method
returns a non-zero error value on failure
and 0 on success.
</p>
<b>Parameters</b> <br>
 <b>h_nelemp</b><ul compact><li>The DB-&gt;get_h_nelem method returns  the
estimate of the final size of the hash table in <b>h_nelemp</b>.</ul>
<br>
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<br><b>Class</b>
<a href="../api_c/db_class.html">DB</a>
<br><b>See Also</b>
<a href="../api_c/db_list.html">Databases and Related Methods</a>
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